Alex Wong1697456877 Posted August 13, 2002 Share Posted August 13, 2002 Any ideas? Was having a good old blat down my fave bit of localish road when a strange noise started coming from the engine bay. It's engine speed related, isn't audible at low revs but over about 3500 and it's very obvious. Sounds like a rasping metal on metal sound and follows engine rev speed. Quite loud as it's clearly audible over the engine and is especially noticable if you blip the engine hard and let it fall to idle. It seems to be coming from the engine although it could be from within the bell housing. Differential diagnosis? The clutch feels fine and the noise is the same with the clutch engaged or disengaged. The engine feels like it's delivering it's normal quota of horses although obviously I didn't thrash it with that noise. Have looked at the plugs, cams, cam followers and they look fine. Don't think it's the release bearing. Nothing obviously loose in the engine bay. Any ideas?? Link to comment Share on other sites More sharing options...
Paul D Jones Posted August 13, 2002 Share Posted August 13, 2002 Alex had a similar noise with my car it turned out to be the little pin that helps to hold the release arm in place the bit that looks like a drawing pin £1.16 for Ford, every thing worked ok just very noisy, then the starter motor started sticking on starting. You can tell if its a similar set up to my car my grabing hold of the release arm and it will rotate a little as aposed to the normal in and out its an engine out job, I was also lucky it had not damaged the clutch other than a few scratches as it had dissapered round the bellhousing. Paul. See My Car Here Link to comment Share on other sites More sharing options...
robmar Posted August 14, 2002 Share Posted August 14, 2002 probably not but... could it be your exhaust hitting the bodywork around the hole in the skin. I only say because I have a very nasty metalic rasping soud that I know is caused by this. One more job on the to do list rob Link to comment Share on other sites More sharing options...
F355GTS Posted August 14, 2002 Share Posted August 14, 2002 Could it be a failed weld or loose bolt on the exhaust bracket, one of the two that bolt the downpipes to the collector? Mark Link to comment Share on other sites More sharing options...
EFA Posted August 14, 2002 Share Posted August 14, 2002 Piston slap.............or big ends.... *wink* Fat Arn Visit the K2 RUM site See the Lotus Seven Club 4 Counties Area Website here Link to comment Share on other sites More sharing options...
I reply to every thread Posted August 14, 2002 Share Posted August 14, 2002 Have you got a Lambda sensor blanking plug in the manifold? Mine came loose & made a real death rattle - Sounded as though it was coming from the back of the block or bellhousing & had me worried for a good 20 mins before I realised what it was. Link to comment Share on other sites More sharing options...
felix.klauser Posted August 14, 2002 Share Posted August 14, 2002 broken/cracked alternator fan rubbing on alternator housing? Link to comment Share on other sites More sharing options...
Peter Carmichael Posted August 14, 2002 Share Posted August 14, 2002 Have you checked that all the pulleys are done up tight. Dropping a pulley would be expensive. If you want to check the big ends, set the engine at 90 deg BTDC. Remove spark plugs, rock the crank with a spanner. If a big end has gone, there will be some evident lash in the movement. Your description of the sound doesn't sound like big ends. Link to comment Share on other sites More sharing options...
scooby dooby doo Posted August 14, 2002 Share Posted August 14, 2002 so the noise is the same whether the engine is under load or not? and you are still getting the normal number of Luton's finest ponies? Sounds like an ancillary related thing then. So alternator, exhaust rubbing, lose wotsit all sound plausible. Try doing blips at a standstill (using throttle linkage) and sticking your ear in various places to locate it. HOOPY Link to comment Share on other sites More sharing options...
Mr Locust Posted August 14, 2002 Share Posted August 14, 2002 Exhaust innards after the packing has blown out? Had this on a stainless box supplied by W*******ld! Link to comment Share on other sites More sharing options...
Mr Locust Posted August 14, 2002 Share Posted August 14, 2002 Exhaust innards after the packing has blown out? Had this on a stainless box supplied by W*******ld! Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted August 14, 2002 Author Share Posted August 14, 2002 Still no diagnosis. Highly unlikely - cams, followers, big ends, ancillaries, bent valve, exhaust, inlet/exhaust manifold Unlikely - release bearing, clutch, injectors Possible - valve spring, throttle pot, valve timing I'm hoping that it's the throttle pot resulting in the timing being to be brought back a bit causing the hot running and detonation. The laptop is going up to Lawn Bank Garage this weekend. ☹️ Link to comment Share on other sites More sharing options...
EFA Posted August 14, 2002 Share Posted August 14, 2002 Alex, Do you have plastic or metal cambelt pullies??? These are a known failure point which has been touched on above. Also the crank pulley bolt should be replaced every time it is undone according to Swindon as they break. Could be loose or broken? Also its not unhead of the spigot bearing breaking up! Fat Arn Visit the K2 RUM site See the Lotus Seven Club 4 Counties Area Website here Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted August 15, 2002 Author Share Posted August 15, 2002 They're metal - have listened to them with an engine stethoscope and they sound fine. They're tight and look fine. Crank pulley looks fine as well. Still don't know...... ☹️ Edited by - Alex Wong on 15 Aug 2002 21:29:47 Link to comment Share on other sites More sharing options...
Gridgway Posted August 15, 2002 Share Posted August 15, 2002 cam belt rubbing? Graham Link to comment Share on other sites More sharing options...
Mr Locust Posted August 15, 2002 Share Posted August 15, 2002 Worn teeth on the pulleys can make a horrible noise when a new belt gets fitted? Link to comment Share on other sites More sharing options...
Mr Locust Posted August 15, 2002 Share Posted August 15, 2002 Worn teeth on the pulleys can make a horrible noise when a new belt gets fitted? Link to comment Share on other sites More sharing options...
andygriffiths Posted August 15, 2002 Share Posted August 15, 2002 Ihad a similar noise when the main bolt holding the alternator on sheared Andy GRIFF Edited by - Andy Griffiths on 15 Aug 2002 23:35:21 Link to comment Share on other sites More sharing options...
Peter Carmichael Posted August 16, 2002 Share Posted August 16, 2002 Possible - valve spring, throttle pot, valve timing I'm hoping that it's the throttle pot resulting in the timing being to be brought back a bit causing the hot running and detonation. If it is hot running and detonation, could it just be a bad tank of fuel?? Peter Loadsachequestubs Carmichael Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted August 16, 2002 Author Share Posted August 16, 2002 Tried 2 alternators - no change. Not fuel as it started mid blat.... Still cogitating... Link to comment Share on other sites More sharing options...
Peter Carmichael Posted August 16, 2002 Share Posted August 16, 2002 Is the ring gear falling off your QED flywheel? Peter *eek*Loadsachequestubs Carmichael Link to comment Share on other sites More sharing options...
Alex Wong1697456877 Posted August 16, 2002 Author Share Posted August 16, 2002 Can see part of the flywheel and it looks fine. The engine was out only 5 days ago and it looked fine then. All ideas welcomed!!! I'm thin on ideas now. Alex Link to comment Share on other sites More sharing options...
Graham Perry Posted August 16, 2002 Share Posted August 16, 2002 Something not fully tightened when you put the engine back in 5 days ago ? I don't know a Vauxhall but are there any plates that cover gaps in the belhousing (like on a crossflow) that might be loose and touching the flywheel Link to comment Share on other sites More sharing options...
ECR Posted August 16, 2002 Share Posted August 16, 2002 You never did find that first set of house keys did you?........... Link to comment Share on other sites More sharing options...
stevefoster Posted August 16, 2002 Share Posted August 16, 2002 Clutching at straws... Starter engager rattling around somehow... Anything to do with the scavenge pump? Steve My racing pics, 7 DIY, race prep. Updated oftenhere Hants (North) and Berkshire area club site here Link to comment Share on other sites More sharing options...
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